Don't scrap it yet! Let's fix it!
Ok the best thing to do is do it in steps:
Step 1:
Spark
1. Do you have spark on all cylinders AND are the appropriate leads going to the appropriate cylinders? Ie from left to right is 1 to 4. If you, by accident put lead 2 on cylinder 1 it's not going to start even if you pray to the Dark Gods in your basement. Be 100% sure that the appropriate leads are going to the appropriate cylinders. Normally they are marked however sometimes the number tape falls off or gets dirty. If they are stock leads they will be numbered. If they are not and the previous owner didn't mark them it gets a little tricky. Are you confident that the leads are going to the appropriate cylinders?(I've screwed this up once before on a few bikes by being inattentive)
2. Spark plugs and gapping: Are you getting a solid spark on all spark plugs and are they gapped properly? If you are unsure(weak spark) and have them gapped properly. Don't gamble just go out and bite the bullet and get a new set of plugs. A spark plug gap tool is like $2 and I carry one underneath my seat so they are not expensive. If they plugs look good make sure they are gapped correctly. I believe the SAE gap is .024 - .028 inches. If the gapping is too small or too large you will get a weak spark.
3. Coils. I know you've said you replaced them, but this is another matter. I have a .pdf service manual version of your bike(I have the same just 2005, pm me for it) which has the coil testing procedure. If you have a decent multi-meter with an Ohm resistance function you can do it yourself. If not, best to maybe bite the bullet and get them tested at a shop. Chances are though, if you have a good spark on all plugs you should be good regardless. Even if not I would buy some new leads and caps before fooling around with the coils. If your confident about the spark, on to step 2:
Fuel/air:
Just a precursor question. I believe in your post that you said you change out the floats and re-installed the carburetors correct? Was there a specific reason why you though that necessary? Did you smell alot of gas? Was there a lack of gas? Or were you just trying to eliminate a possible problem? Please don't think I'm trying to be obtuse or anything I just want to know what you were thinking which may help us diagnose the problem.
When you re-installed the floats did you set them to the correct float height(13mm)? How you measure it is from the top of the carb body(the line after you take the bowls off) to where the float needle is just touching BUT NOT compressing against the float valve. Float height is extremely important especially on little or light throttle operation. I found the best way is to stand the carb bank on its side and gently tilt the bank until the floats get resistance from the float needle to the needle valve then measure from there. Since I have the same bike the float height or distance from the top of the float body(the split after you take the bowls off) to the lower most part of the float(they are curved) should be 13 mm +- 1.0mm. If you need instruction please pm me and I'll help you out or I'll even at the end of this post my real email address as I get so much spam it won't matter if you email me. It's VERY important.
1. Ok lets say that the float height is correct or at least within the ballpark. Let's break down the fuel delivery system so that you can see if the petcock/vacuum tube may be causing an issue:
1. Disconnect the tank and vaccuum tube from the petcock side not the carburetor side.
2. Once the tank is off, create a temporary fuel tank by buying a half liter of coke or some other plastic bottle. What I did was get some 1/4 inch clear tubing and drill a hole in the cap of the bottle and seal it with some silicone or hell even duct tape, and pop in the tubing. It's going to last maybe a few days for testing. The vacuum line for the petcock will be on number 4. You need to plug that. I use just a short 1/4 bit from any number of multi-bit screwdrivers. If not you will be lagging like crazy on that cylinder.
3. What the general gist is. Is you want to feed the carburetors manually by squeezing the bottle only as necessary(if it back blasts stop) which will enable you to determine what the the carburetors are doing when they are feed properly without having the weight or the fuel flow of a whole full tank of gas in case the petcock is faulty(mine was, since rebuilt it)
4. If the squeeze bottle is not to your liking you can recruit a friend to help you by getting a fairly large funnel, attaching it to the fuel line and hold it up(so it doesn't spill) duct taping the funnel and the fuel line together temporarily and doing the test again.
Starting instructions:
With the fuel system isolated and you've either filled the fuel line with fuel and up to half of the funnel can take:
1. Thottle OFF
2. Choke out to almost full
3. Hit the starter for no more than 10 secs continuously at a time
4. If the engine catches, still no throttle, adjust the choke to keep RPM's under 2500 RPM
There are a few more tricks in the bag and if you need some more help there are alot of people here to help you out. If you need the service manual email me at:
christechpro@gmail.com
We can even talk on the phone if you wish I've helped a few guys here out that way. It doesn't sound catastrophic, it's probably some bullshit problem that can be fixed easily as these engines are VERY hard to kill. I hope this helps,
Chris
Topic: Sick Bandit 1200s (Read 10715 times)